Steam-engine



(No Mbdel.) 2 Sheets-Sheet 1.

J. W. ,SARVGEINT.

STEAM ENGINE.

No. 502,763. Patented Aug. 1893.

zf gjfg v R 13h J0 2 Sheets-Sheet 2. J. W. SARGBNT.

V STEAM ENGINE.

Patented Aug. 8, 1893.

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UNITED. STATES PATENT OFFICE;

JOHN W. SARGENT, OF SORANTON, PENNSYLVANIA.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 502,763, dated August 81893.

Application filed April 13, 1893. Serial No. 470,223. (No model.)

To all whom it may concern:

Be it known that I, J OHN W. SARGENT, a citizen of the United States,residing at Scranton, in the county of Lackawanna and State ofPennsylvania, have invented certain new and useful Improvements inSteam-Engines, of which the following is a specification.

My invention relates to an improvement in steam engines and it consistsin a novel and convenient arrangement of the valves and valveconnections upon a compound engine in which the cylinders are arrangedtandem.

The objects of the invention are to arrange the cylinders and steamchests as compactly as possible and at the same time to provide for theready removal of the steam chest heads or bonnets so that the valves maybe easily inspected or taken out for repairs; and furthermore to operatethe valve and steam chests of a tandem engine from a single crosshead.

In the accompanying drawings, Figure l is a plan view of part of avertical engine embodying my invention. Fig. 2 is a front elevation ofthe same, and Fig. 3 is a side elevation, one of the steam chests beingbroken away to show the crosshead and its connections.

In the drawings I have shown a pair of cylinders, arranged tandem, withtheir steam chests and so much of the engine as is necessary toillustrate my present invention. These cylinders may constitute a partof an ordinary compound engine or they may be used as two of thecylinders of a triple or quadruple expansion engine, the particularvariety of engine being immaterial so far as the present invention isconcerned.

As shown 1 indicates a low pressure cylinder which rests directly uponthe column 2 of the engine frame and is provided with a pair of pistonvalves inclosed in steam chests 3-3. The high pressure cylinder 41sdirectly above and in line with the low pressure cylinder. The steamchests 33 of the low pressure or double-valved cylinder are separatedfrom each other a distance about equal to the width of the steam chest 6of the high pressure or single-valved cylinder so as to permit of theremoval of the lower bonnet 7 of the latter steam chest.

The reference signs 8 and 9 indicate respectively the inlet. and outletports of the several steam chests.

The valve stems 10 of the low pressure valves are connected to theextremities of a crosshead 11 which slides upon guides 12 upon thecolumn ,2. This crosshead is provided centrally with an arm 13 whichextends upward between the steam chests 33 and runs upon a guideway 14:attached to the low pressure cylinder. To the upper end of the arm 13 isconnected the valve stem 15 of the high pressure cylinder. The crosshead11 is operated by a link 16 the lower end of which is connected with thevalve gear. The valve stem crosshead, including its Vertical arm, is ofan inverted T-shape and the guides upon which it runs are arranged atthe apices of a triangle, thus giving the crosshead a smooth and steadymovement without undue strain upon any of the parts. The three valvechests when arranged as described permit the upper and lower bonnets ofeither of them to be removed without interference from the others; andby providing the low pressure cylinder with two steam chests the largevolume of expanded steam is permitted to enter the cylinder unimpeded,the engine is rendered more compact and shapely than if a single steamchest were used, and provision is made for a direct connection betweenthe crosshead and the stem of the high pressure valve, which connectionis directly in line with the link operating the crosshead. As shown thearm 14 is bolted to the main crosshead 11, but it will be evident thatif desired they may be cast'in a single piece. The valve stem 15 isconnected to a lug 17 at the rear of the arm 13, and the link 16 isconnected by a pin 18 v to lugs 19 upon the rear of the crosshead 11.These and other details of construction may however be varied to suitany particular re quirements without departing from the spiritof myinvention. a

What I claim, and desire to secure by Letters Patent, is

1. In a steam engine the combination of a double-valved cylinder and'asingle-valved cylinder arranged tandem, the steam chests of the formercylinder being separated and arranged with the space between themopposite the steam chest of the latter cylinder,

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and a single crosshead to which each of the valve stems of saidcylinders is connected, substantially as described.

2. In a steam engine the combination of a double-valved cylinder and asingle-valved cylinder arranged tandem, the steam chests of the formercylinder being separated and arranged with the space between themopposite the steam chest of the latter cylinder, and a crosshead havingits extremities connected to the valve-stems of the double-valvedcylinder and acentral arm ezitending between the steam chests of saidcylinder and connected to the valve stem of the single-valved cylinder,substantially as'described.

3. In a steam engine the combination of a double-valved cylinder and asingle-valved cylinder arranged tandem, the steam chests of the formercylinder being separated and arranged with the space between them oppo-20 site the steam chest of the latter cylinder, and a crosshead having acentral arm arranged between the steam chests, of a double-valvedcylinder, the said crosshead being provided with guides 12 and a guide14: for the arm, 25

